Acoustic telemetry involves acoustic devices (or tags) commonly used to monitor behavior of fish. Acoustic tags transmit a sound signal that transmits identification, location, and other information about a tagged fish to a receiver at a selected pulse rate interval (PRI), or “ping” rate. The receiver detects signals emitted by the acoustic tag and converts the sound signals into digital data. Post-processing software then processes the digital data and provides location information about the tag and thus the behavior of the fish when the receiver detects the sound signal. By identifying the signature of the acoustic signal a specific animal may be identified, which allows tracking the behavior of the host. Acoustic data may be used, e.g., to estimate survival of fish through dams and other routes of passage. However, conventional transmitters are too large for small hosts (30-100 g mass and 180-270 mm length), have short lifetimes, and/or have an inadequate transmission range that to date have precluded intensive research of small hosts such as juvenile sturgeon using acoustic telemetry techniques. Recently, an injectable acoustic tag was developed for the U.S. Army Corps of Engineers for tracking juvenile salmon detailed in U.S. patent application Ser. No. 14/014,035 filed 29 Aug. 2013, and other acoustic tags for tracking other small hosts detailed in Patent Application No.: PCT/US14/53578 filed 29 Aug. 2014, which references are incorporated herein in their entirety. The injectable acoustic tag works well for tracking yearling Chinook salmon in river systems. However, it is not optimal for long-term monitoring of hosts requiring a stronger acoustic signal and longer service life including, e.g., juvenile (<1 year old) sturgeon. Accordingly, new tag designs are needed that reduce the overall size, mass, and/or volume, that enhance the power source voltage, tag lifetimes, and transmission range, and reduce adverse effects and costs associated with attachment (which includes implantation) thus broadening the range of potential applications including, e.g., investigating behavior and habitat of juvenile sturgeon and other small species. The present invention addresses these needs.